ABSTRACT The purpose of the proposed study is to develop and pilot the implementation of a short-form HIV-specific disability questionnaire to promote healthy aging among adults aging with HIV. Specific aims are: 1) To develop and assess the utility of a new short-form HIV-specific disability questionnaire across multiple clinical practice settings with older adults with HIV, and 2) To pilot the implementation of the new short-form HIV-specific disability questionnaire, and assess its measurement properties while collecting foundational data on the presence, severity and episodic nature of disability among adults aging with HIV and multimorbidity in the United States, Canada and Ireland. Standardized patient reported outcomes (PROs) designed to capture the nature and extent of disability and its fluctuation over time are critical to guide the provision of timely and appropriate care for adults aging with HIV. In an earlier phase of work, we developed a 69-item Patient Reported Outcome (PRO), called the HIV Disability Questionnaire (HDQ) and demonstrated its reliability and validity among adults living with HIV in Canada and Ireland. As an increasing number of adults age with HIV and multimorbidity, there is a critical need for a brief yet comprehensive assessment of disability that can be routinely and easily administered across health systems in clinical practice. In Phase 1 of this study, we will use psychometric (Rasch analysis) and clinical approaches to develop a short-form version of the HDQ (SF-HDQ). We will then use a combination of quantitative (questionnaires) and qualitative (interviews) with adults aging with HIV and HIV health providers to assess sensibility (face and content validity), utility, and optimal use of the SF-HDQ in clinical practice across three clinical sites in Denver Colorado, Toronto Canada and Dublin Ireland. In Phase 2, we will conduct a cross-sectional pilot study to examine the implementation and assess the measurement properties of the SF-HDQ with adults aging with HIV across the three health systems. Outcomes will yield the first known short form HIV-specific disability PRO developed through international, academic-community collaboration to assess prevalence and impact of episodic disability. Future universal measurement of disability may contribute to ongoing clinical management, specifically tracking of episodic disability trends and evaluation of interventions to inform allocation of resources to better promote healthy aging with HIV.